Abstract
In this research, a probabilistic model was applied to a building model of a public building located in Bolzano, Italy, for the assessment of the airborne contagion risk due to Covid-19. Different ventilation strategies were investigated in terms of risk reduction, as well as the effectiveness of the Pfizer vaccine. TRNSYS and TRNFLOW models of the public building were created to evaluate the internal airflows, necessary to calculate Covid-19 concentrations in the offices. Both building and airflow models were calibrated against measurement data collected with temperature sensors located in some of the building offices and hallways, prior to coupling with a Monte Carlo model for the risk assessment process. The results were reported in terms of infection risk, both for occupants located in the same office, as well as for occupants in adjacent spaces. It was observed that the current operational modes of both natural and mechanical ventilation are able to limit the spread of Covid-19 only in case of vaccination coverage presence and if the Delta variant is considered. If vaccination coverage is not present or if the Omicron variant is concerned, a higher frequency of windows opening, and a schedule based on occupancy profiles for mechanical ventilation should be adopted.